Inspection Procedures for Effective GPR Surveying of Buildings

A considerable number of studies about GPR applications in building inspection can be found in the literature. New advances in software development, laboratory tests under controlled conditions and numerous cases studies are representative works in this field of knowledge. Some applications are focused on rebar detection, on concrete building assessment, and in modern masonry structures. However, the majority of the works are focused on cultural heritage buildings evaluations, presenting interesting and diverse cases studies. Remarkable results can be found about cracks detection and inspection of masonry walls and columns. Software development has been focused, in many cases, to the enhancement of radar images to facilitate data interpretation. In other cases, synthetic models have been developed to compare results with GPR images from complex scenarios. Evaluations of quantitative properties of constructive materials have been developed based on laboratory tests. Other special works have been also based on laboratory tests: damp measures, concrete degradation due to corrosion, and damages due to tree roots are tested in laboratory specimens under controlled conditions. Although it is a promising subject, few studies have been applied in buildings, revealing the difficult inherent to these complex scenarios. Open issues have been defined as a final conclusion based on the revision of different works. Developments of radar imaging, models and new applications seem to be the most relevant future lines in the GPR building inspection, probably based in a proper and complete definition of casuistic and requirements in structures evaluations.